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Post by hellocontrol on Jul 13, 2014 15:13:20 GMT
I have seen a photo of a signal plate W200 with an arrow underneath Now I have racked my brain and I can not remember this signal going by the plate it is for a shunt signal normally. Nortube or someone will be able to help.
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Post by railtechnician on Jul 13, 2014 17:26:49 GMT
I have seen a photo of a signal plate W200 with an arrow underneath Now I have racked my brain and I can not remember this signal going by the plate it is for a shunt signal normally. Nortube or someone will be able to help. It certainly looks like a shunt signal plate but I don't recall it either. Mind you I haven't worked at Tooting Broadway since I ran all the leaky feeder cables and installed all the Texscan amplifiers in the running tunnels for the trial Victoria line train radio system between Tooting Bec and Colliers Wood circa 1990.
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Post by hellocontrol on Jul 14, 2014 6:25:11 GMT
I know they put in train stops in the sidings after a number of accidents they also put on the yellow lights now did they put a shunt signal and then remove it ?
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Post by Nortube on Jul 14, 2014 12:33:20 GMT
Tooting Broadway sidings. If I recall correctly, the plate is on the tunnel wall, on the right when facing the rear of the tunnel and the arrow points towards the rear.
It is approximately in the position where the policeman is for a train entering the siding. W2B is the shunt signal to enter the siding from the SB platform (W3B to enter from the NB platform). I can't ever recall there being a shunt signal there, certainly not since I joined in 1973, and there is nothing shown on the roller diagram from around 1939+.
From what I recall, dead-end sidings had fixed yellow lights on the tunnel wall to remind drivers they were entering a dead end. This was done following where a reversing train ran straight into the rear at Tooting and the driver was killed (1971?), so there wasn't a policeman there then. I believe policemen were put in sidings etc. following the Moorgate crash
I suspect that it may just be a signal plate for the policeman, even though there is no signal. I've seen similar plates elsewhere in similar circumstances.
I'll have a did around later and see what I can find.
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Post by Nortube on Jul 14, 2014 13:13:56 GMT
Was going to look later, but decided to have a look at the changes to the siding now:
18 November 1960 "Sand drag added"
27 September 1961 "12' Sth buffer stop warning lamps added to siding"
11 September 1962 "Additional warning lamps added in siding"
15 Aug 1972 "W200 added in Tooting Broadway siding"
3 March 1973 "W200 signal removed"
I'm not sure if the warning lights that are referred to are the yellow tunnel lights, if so, that's before the crash.
There is no specific mention of the policeman being added to the siding, so I'm assuming that W200, when added in 1972 was a draw-up signal to ensure that a train couldn't proceed at full speed (as part of the changes to dead-end working after the crash). This was possibly an interim measure (perhaps to get drivers used to slowing down) as, for whatever reason, it was then decided to remove the signal, just leaving the policeman doing exactly the same job.
There were no other protection measures added later.
What is surprising is that how long it took to add the added protection of a sand drag. I think that Not all sidings have sand drags, especially where the siding tunnel is long and there is a fixed trainstop at the normal train stopping mark, there just being a buffer at the end of the tunnel.
Also surprising, is that siding overrun detection wasn't installed until 1994.
Archway I've had a quick look at Archway for comparison. Archway was designed as a nine car siding. It was originally the NB overrun tunnel when Archway (or Highgate as it was known then) was the terminus.
To the best of my knowledge, nine car trains never ran on the Barnet branch, even though the new platforms at Highgate Low Level were designed for it. Therefore, other than perhaps an occasional long engineers train, the full length of the siding would never be used for reversing in.
Protection Sand drag added in 1950 Fixed yellow lights added at some point between 1961 and 1965 (presumably around the same time as Tooting Broadway) Siding protection added in 1973. Presumably this is the policeman, but no mention of an actual draw-up signal Overrun detection added in 1994
Considering the length of the siding and that it wasn't being used by nine car trains, it's surprising that the sand drag was added 10 years earlier than Tooting, unless they were still thinking about the possibility of long trains then. As overrun detection was added here at the same time. I assume that it was a general thing being done to sidings.
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Post by hellocontrol on Jul 14, 2014 16:09:29 GMT
Nortube thanks I thought that the siding lights were before Moorgate as I remember, there was a train checker can't remember his name but he was the one who had his foot caught in a previous collision at Tooting siding.
I worked on the Northern between 1972-1976 and can not remember a W200 but looking at what you have written it was not there very long and the turns we had there were no reversers only when the service was screwed.
I have checked my notes and yes Archway was 500' when it opened but was reduced to 471' in later years while Tooting was 375' I don't know if that was the same as when it opened though.
I can not remember anywhere else where there was a shunt signal like W200 a lot of sidings were given speed train stops, I suspect the detection in 1994 was to alert the supervisor like they did at quite a few sites.
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Post by railtechnician on Jul 14, 2014 17:03:01 GMT
Nortube thanks I thought that the siding lights were before Moorgate as I remember, there was a train checker can't remember his name but he was the one who had his foot caught in a previous collision at Tooting siding. I worked on the Northern between 1972-1976 and can not remember a W200 but looking at what you have written it was not there very long and the turns we had there were no reversers only when the service was screwed. I have checked my notes and yes Archway was 500' when it opened but was reduced to 471' in later years while Tooting was 375' I don't know if that was the same as when it opened though. I can not remember anywhere else where there was a shunt signal like W200 a lot of sidings were given speed train stops, I suspect the detection in 1994 was to alert the supervisor like they did at quite a few sites. Archway tunnels and siding is one piece of Northern line tunnel that I never worked in. I recall being told back in the 1980s by the Post Run Inspector, when we were both based at South Woodford in the Portakabins at the end of the station car park, that Archway siding was unique as it had a track circuit which was a Pi-Delta. I have never heard of such a track circuit either before or since. ISTR he said it was something to do with the long length of the siding but I know nothing at all about it. Mention of the siding jogged a long lost memory so I'm wondering if anyone can throw any light upon it.
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Post by hellocontrol on Jul 16, 2014 6:24:16 GMT
Archway tunnels and siding is one piece of Northern line tunnel that I never worked in. I recall being told back in the 1980s by the Post Run Inspector, when we were both based at South Woodford in the Portakabins at the end of the station car park, that Archway siding was unique as it had a track circuit which was a Pi-Delta. I have never heard of such a track circuit either before or since. ISTR he said it was something to do with the long length of the siding but I know nothing at all about it. Mention of the siding jogged a long lost memory so I'm wondering if anyone can throw any light upon it. I have never heard of a Pi-Delta that's a new one on me and having done a search I can't find anything.
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Post by railtechnician on Jul 16, 2014 11:45:30 GMT
Archway tunnels and siding is one piece of Northern line tunnel that I never worked in. I recall being told back in the 1980s by the Post Run Inspector, when we were both based at South Woodford in the Portakabins at the end of the station car park, that Archway siding was unique as it had a track circuit which was a Pi-Delta. I have never heard of such a track circuit either before or since. ISTR he said it was something to do with the long length of the siding but I know nothing at all about it. Mention of the siding jogged a long lost memory so I'm wondering if anyone can throw any light upon it. I have never heard of a Pi-Delta that's a new one on me and having done a search I can't find anything. The only Greek alphabet track circuits I am aware of were beta tracks as on the Victoria line and delta tracks (about six different types) used on all lines. The Post Run Inspector was Bob Carter whose signal maintenance area included Archway when he was an AET. He was the only person I ever heard mention a Pi-Delta track and he did say it was the only one in existence. It has intrigued me ever since he told me of it 30 years ago, unfortunately he did not talk about it in detail. I have no reason to doubt him, he was not the kind of person to mislead one and we had many interesting lunchtime chats about various aspects of signals and communications. At the time I was in the training division, as the Comms installation and maintenance instructor, having served in both Signals New Works and Telephones New Works, all my peers at South Woodford training school and Earls Court training school were drawn from signals departments as were those in our offices at 10A Wood Lane who included the signals DO course instructors and our boss who had been head of the Development section and yet I never thought to raise the subject with any of them.
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